Could some experienced graphic designer suggest what tools to use- what software, to do this- make a picture of some money bills, which are curved and floating around randomly, with some background texture- golden coins maybe. Can you do this with Adobe Photoshop Elements (the cheaper version of Adobe Photoshop)?
It depends what look you want to achieve and what you will be using it for.
If you want realistic-looking bills and coins, then you should use a photo-editing software, like Adobe Photoshop. Adobe Photoshop Elements or other editing software may work if it has a decent warp tool. I think the best way to create the floating look would be to use a warp tool to pull the corners of the bill to the proper positions, and it will take some work to make sure it doesn't look stretched or warped.
If you are creating this for anything other than personal use, you need to make sure that you have proper permissions to use the images you select. You could easily take this photos yourself, or you could use some stock images.
For the background, you could use a similar image, and duplicate it, rotate it, add effects - all of which can be done in most editing softwares, including Photoshop Elements. You may also be able to find a stock image with the text you want.
The other type I had in mind is if you wanted something created from scratch, or a sketched image. For this, you would need Adobe Illustrator, a drawing tablet, or another type of drawing program. Illustrator is a bit confusing for beginners, but once you understand the basics, it is pretty easy to pick up.